1,069 research outputs found

    Transducer electronic data sheets: anywhere, anytime, anyway

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    Transducer electronic data sheets (TEDS) are a key element of smart transducers because they support core features such as plug and play, self-calibration, and self-diagnostics. The ISO/IEC/IEEE 21451-4 standard defines templates to describe the most common types of transducers and suggests the use of one-wire memories to store the corresponding data. In this paper we explore new ways to store and access TEDS tables, including near field communication (NFC) tags and QR codes. We also present a mobile TEDS parser, compatible with Android, that is capable of reading TEDS data from all supported mediums (one-wire memories, NFC tags, and QR codes) and decoding them as human-readable text. The idea is to make TEDS available in the easiest way possible. We also underline the need to extend the 21451-4 standard by adding support for frequency-time sensors. A new TEDS template is proposed, and filling examples are presented. The main novelties of the paper are (i) the proposal of new ways to store 21451-4 TEDS tables using NFC tags and QR codes; (ii) the release of new tools to access TEDS tables including a mobile parser; and (iii) the definition of a new TEDS template for frequency-time sensors.info:eu-repo/semantics/publishedVersio

    Diatoms of temporary and permanent watercourses in Southern Europe (Portugal)

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    The potential importance of benthic diatoms in Mediterranean watercourses has received limited academic attention historically. This study sought to provide baseline information for this poorly studied group. Temporary and permanent watercourses in Portugal differ in catchment characteristics, climatic variables and water chemistry. The benthic diatom communities were characterized in terms of ecological preferences and conservation status for taxa with relative abundance above 1% in at least one site covering 39 temporary sites (109 taxa) and 53 permanent sites (130 taxa). The low-profile guild dominated both temporary and permanent watercourses, followed by the high-profile and motile guilds. Indicator value analysis indicated that Amphora copulata, Cocconeis placentula, Diploneis separanda, Encyonopsis subminuta, Fragilaria radians, Gomphonema olivaceum, Gomphonema truncatum, Halamphora veneta, Navicula radiosa, Navicula veneta, Sellaphora seminulum and Ulnaria acus were indicators of temporary watercourses, whereas Encyonema minutum, Eunotia minor, Fragilaria rumpens, Fragilaria cf. socia and Navicula rhynchocephala were characteristic of permanent watercourses. Ecological preferences of indicator taxa were inferred on the basis of environmental variables that differed significantly between temporary and permanent watercourses. The importance of temporary watercourses for the maintenance of diatom biodiversity is discussed and explored

    Homogeneous Ziegler-Natta polymerisation: A kinetic approach .2. Transient-state kinetics

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    An integrated view is presented of several possible mechanisms applicable to the interpretation of homogeneous Ziegler-Natta polymerisation. In this paper, the transient aspects related to the kinetics of Ziegler-Natta polymerisation are investigated. Extensive data are used to construct kinetic profiles (rM vs. t) from a theoretical approach. Special attention is given to the duration of the transient period as a function of the different kinetic parameters. The kinetic models developed are fitted to experimental data, either directly obtained by the authors or published in the literature. These general models have a broad range of application.info:eu-repo/semantics/publishedVersio

    A kinetic approach to homogeneous Ziegler type polymerization. Transient state

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    In this paper we present a kinetic approach to the analysis of transient-state homogeneous Ziegler-Natta polymerization activity data. The main features of the experimental data are discussed and fitted to transient kinetic models.info:eu-repo/semantics/publishedVersio

    Polymerization of ethylene using metallocene and aluminoxane systems

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    This paper describes ethylene polymerization using a number of metal-locene and aluminoxane catalyst systems, Cp2MR2 and methylaluminoxane [M = Zr, W, Nb; R = Cl, CH3]. Two types of methylaluminoxane, MAO (1) and MAO (2), were used as cocatalysts. The polymerization activities of the complexes Cp2WCl2 and Cp2NbCl2 were compared with that of Cp2ZrCl2. The Nb and W complexes were found to be less active than the Zr complex. Polyethylene characterization was also carried out by the following methods: gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR).info:eu-repo/semantics/publishedVersio

    Percolation of strings and the first RHIC data on multiplicity and tranverse momentum distributions

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    The dependence of the multiplicity on the number of collisions and the transverse momentum distribution for central and peripheral Au-Au collisions are studied in the model of percolation of strings relative to the experimental conditions at RHIC. The comparison with the first RHIC data shows a good agreement.Comment: RevTeX, 11 pages, 4 eps figures included using epsfi

    Characterization of aroma compounds in Portuguese extra virgin olive oils from Galega vulgar and Cobrançosa cultivars using GC-O and GC-x-GC-ToFMS

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    Aroma compounds of virgin olive oils extracted from two olive cultivars – Galega Vulgar and Cobrançosa – grown in Beira Baixa region in central Portugalwere investigated. Gas chromatography–olfactometry (GC–O) was carried out to select the important odorants for subsequent comprehensive gas chromatography/time of flightmass spectrometry (GC × GC–ToFMS) analysis. By GC–O fifteen odorants were identified. For the quantification of volatile compounds, headspace solid phasemicroextraction (SPME) techniquewas optimized. Under optimized conditions, 22 volatile compounds were quantified in all samples. Trans-2-hexenal was the most abundant compound. A discriminant analysis (DA) was used to discriminate among olive oil samples obtained from olives of the two cultivars with different harvest time/ripening stages. Concerning the harvesting time and cultivar, nine volatiles showed to have discriminant power among samples, namely heptanal, trans-2-hexenal, 1-octen-1-ol, nonanal, 2,3-butanedione, ethyl-2-methylbutyrate, hexanal, cis-3-hexenylacetate and 3-methylbuthylacetat

    Studi Komparasi Hasil Belajar Antara Mahasiswa Yang Berorientasi Untuk bekerja Dengan Yang Berminat Melanjutkan Studi Pascasarjana Pada Mahasiswa Pendidikan Akuntansi FKIP UMS Angkatan 2014 Universitas Muhammadiyah Surakarta

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    This study aims to determine whether there are differences in learning outcomes between students who are oriented to work with those who continue to pursue postgraduate studies in Accounting Education students Faculty of Teacher Training and Education UMS class of 2014. This thesis uses quantitative research through a comparative method. The total population of the study was 102 students with a sample size of 78 students using the help of the Krejcie table with an error rate of 5%. Sample selection uses the Probability Sampling technique of simple random sampling. Data was collected using the questionnaire method with Likert scale and documentation. Test requirements analysis using normality test and homogeneity test. The analytical method used is the t test or T-test. The results of t-test calculations at the level of significance obtained t value of 0.390, while t-table at the 5% significance level with Degree of freedom (76) is 2000. Due to tcount <t table (0.390 <2000) then H0 is accepted, which means there are no differences in learning outcomes between students who are oriented to work with students who are interested in continuing postgraduate studies in accounting education students Faculty of Teacher Training and Education UMS class of 2014. From the analysis above, it can be seen that the orientation differences between students who want to work with those who want to pursue postgraduate studies do not affect the activities of the two groups of students in achieving learning outcomes (GPA)

    Dried brewers’ grain as a replacement for soybean meal on nutrient digestibility and rumen parameters of cattle

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    The objective of this study was to determine the effect of replacing soybean meal with dried brewers’ grains (DBG) in intake and digestibility of the nutrients and the ruminal parameters of cattle. Four ruminal cannulated Jersey oxen with initial body weight of 662.7 ± 85.5 kg were distributed in a 4x4 Latin square design. The treatments were levels of 0%, 33%, 66% and 100% DBG replacing soybean meal in the diet. Dry matter (DM) and crude protein (CP) intake were not influenced by the treatments. There were linear increases in ether extract (EE), neutral detergent fibre (NDF) and acid detergent fibre (ADF) intakes because of higher levels of these nutrients in diets with DBG. Non-fibre carbohydrate (NFC) and total digestible nutrient (TDN) intake showed a decreasing linear effect. Dry matter and NFC digestibility decreased linearly with rising DBG levels, while EE, CP, NDF and ADF digestibilities were not affected. Ruminal pH was not influenced by DBG levels in the diet. There was a quadratic effect in ammonia nitrogen (NH3-N) concentration in the rumen, with the maximum occurring at a level of 36.7% DGB. The replacement of soybean meal with DBG in cattle diets did not alter DM intake and ruminal pH, but reduced TDN intake.Keywords: Ammonia nitrogen, by-product, digestibility, intake, p
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